head to head
Neither is simply harder - they are hard in different places. FIFA Manager 14 demands more variance; Portal 2 demands more execution.

Optimization · Pure Optimization
A football management sim testing squad-building, finance and tactical optimization.

Optimization · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.
FIFA Manager 14 leans Optimization (Pure Optimization); Portal 2 leans Optimization (Pure Optimization).
Portal 2 leans clearly harder on execution.
FIFA Manager 14
Menu-driven management, no physical input skill
Portal 2
Portal placement requires some precision but timing is lenient.
FIFA Manager 14 leans clearly harder on reads.
FIFA Manager 14
AI clubs follow scripted logic, no real adaptation
Portal 2
No opponent; puzzles are static.
FIFA Manager 14 leans clearly harder on variance.
FIFA Manager 14
Match results and injuries carry simulation randomness
Portal 2
Puzzles are deterministic with no randomness.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
FIFA Manager 14
Squad, finance and tactics planning dominates entirely
Portal 2
Solving the puzzle's logic IS the entire game.
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.